(1) obligations which are secured by adequate collateral security and bear fixed interest if during each of any three, including the last two, of the five fiscal years next preceding the date of acquisition by the insurer, the net earnings of the issuing, assuming or guaranteeing institution available for its fixed charges, as defined in section 556 of this title, have been not less than one and one-fourth times the total of its fixed charges for such year. In determining the adequacy of collateral security, not more than one-third of the total value of such required collateral shall consist of stock other than stock meeting the requirements of section 558 of this title;
(2) fixed interest bearing obligations, other than those described in paragraph (1) of this section, if the net earnings of the issuing, assuming or guaranteeing institution available for its fixed charges for a period of five fiscal years next preceding the date of acquisition by the insurer have averaged per year not less than one and one-half times its average annual fixed charges applicable to such period and if during the last year of such period such net earnings have been not less than one and one-half times its fixed charges for such year; or
(3) adjustment, income or other contingent interest obligations if the net earnings of the issuing, assuming or guaranteeing institution available for its fixed charges for a period of five fiscal years next preceding the date of acquisition by the insurer have averaged per year not less than one and one-half times the sum of its average annual fixed charges and its average annual maximum contingent interest applicable to such period and if during each of the last two years of such period such net earnings have not been less than one and one-half times the sum of its fixed charges and maximum contingent interest for such year.